Build a new TokenCacheService so I can stop using TokenService for something it wasn't designed for.

google_apis/gaia/gaia_constants.h

Index: google_apis/gaia/gaia_constants.h
diff --git a/google_apis/gaia/gaia_constants.h b/google_apis/gaia/gaia_constants.h
index d3aac05cb6f9193bb63eb274d030aa3c1356b1ac..9e3b9af55a1635dedfcd3101f08e92e1f47906d7 100644
--- a/google_apis/gaia/gaia_constants.h
+++ b/google_apis/gaia/gaia_constants.h
@@ -7,6 +7,8 @@
 #ifndef GOOGLE_APIS_GAIA_GAIA_CONSTANTS_H_
 #define GOOGLE_APIS_GAIA_GAIA_CONSTANTS_H_
 
+#include "base/basictypes.h"
+
 namespace GaiaConstants {
 
 // Gaia sources for accounting
@@ -35,6 +37,8 @@ extern const char kGaiaOAuth2LoginAccessToken[];
 
 // Used to construct a channel ID for push messaging.
 extern const char kObfuscatedGaiaId[];
+// How long to keep an obfuscated Gaia Id in an internal cache, in milliseconds.
+extern const int64 kObfuscatedGaiaIdTimeout;
 
 // Used to build ClientOAuth requests.  These are the names of keys used in
 // the json dictionaries that are sent in the protocol.